The invention relates to an apparatus for dispensing a beverage, such as beer or soft drinks, and comprising a container for storing the beverage, a gas source for via a gas conduit supplying the container with a propellant under pressure, a riser pipe serving for leading the beverage out of the container under the action of the above positive pressure and having an open, first end immersed in the beverage and an opposite, second end fluid-communicating with a faucet for drawing the beverage.
Beverages such as beer and soft drinks are largely distributed to restaurants and similar public houses in transportable containers under pressure by a propellant normally consisting of CO2 or at least having a considerable content of CO2.
The propellant keeps the beverage fresh and effervescent and furthermore serves for via a riser pipe expelling the beverage from the container at drawing.
Conventionally, such a container is provided with a double valve with two fluid passages. The valve is opened by means of a coupling that is mounted on the double valve. When the valve is open, the container is via one of the fluid passages in open communication with a compressed-gas source, e.g. compressed-gas cylinder or cartridge connected to the coupling via a reduction valve whereas the riser pipe via the second fluid passage is connected to a faucet connected to the coupling.
At actuation of the faucet the beverage is expelled by the gas overpressure in the container via the second fluid passage and the faucet into a drinking glass to be served to the guest. At the same time the container is via the first fluid passage filled with new propellant in replacement of the expelled beverage.
For practical reasons, the containers that are conventionally utilized in public houses normally contain an adequately large quantity of beverage that typically can be 25 or 50 liters.
The thus known apparatuses are popular and are largely used for serving among other things draught beer.
Draught beer is generally served with a rather limited amount of foam. It is the beer that the guest has to pay for and it is therefore not in the guest""s interest that a larger or smaller part of the paid beer is replaced by airy foam.
However, the foaming process can only be controlled with difficulty. This is due to the inherent physical fact that the pressure in the beer necessarily has to drop suddenly from the positive pressure in the container to atmospheric pressure at discharge from the faucet.
Thereby, the gas dissolved in the beer is liberated forming large amounts of gas bubbles that are very stable due to the large surface coefficient of the beer. Or in other words the beer will foam excessively and will only resettle slowly as the gas bubbles burst.
The operator can try to reduce this unfavorable foaming tendency by manipulating the faucet so that the drawing will pass off slowly. Thereby, costly working time is however lost just as the guestxe2x80x94often impatientlyxe2x80x94will have to wait to get the ordered glass of beer.
Another method of controlling the foaming problem is to draw the beer in several turns with intermediate periods for giving the formed foam a chance to settle. However, this method is also time and labor-intensive and the guest still has to wait for the beverage.
In order to save time and avoid the guest having to wait, some operators draw the beer rather quickly. The relatively large amounts of foam formed thereby are then successively brushed off by means of a stick with the result that foam and with it not unimportant quantities of beer are wasted. The method is quick but the quickness is obtained at the expense of economy.
Thus, there is a need for an apparatus that overcomes the problems and disadvantages of the prior art.
The present invention now provides an apparatus for dispensing a beverage such as beer or a soft drink and is arranged in such a way that the beverage is drawn forcedly with a preset degree of foaming. In addition, this apparatus is of a simple and inexpensive construction. In particular, the apparatus can be quickly and easily installed and operated. In particular, the apparatus is arranged to distribute relatively small quantities of beverage.
These advantages are provided in an apparatus that includes a container for storing the beverage, a gas source and gas conduit associated with the container for supplying the container with a propellant under pressure, a faucet for drawing the beverage from the container, a riser pipe for leading the beverage out of the container under the action of the pressure and having an open, first end immersed in the beverage and an opposite, second end in fluid-communication with the faucet, and a nonreturn valve arranged to offer considerable resistance against flow of propellant into the container and to cause the pressure in the container to drop during the dispensing process.
Preferably, the fluid conduit is arranged to during drawing offer a sufficiently great resistance against flow of beverage that the beverage leaves the fluid conduit with a positive pressure of between 1% and 50% of the positive pressure in the container. Also, if desired, the device can also include a reduction valve located between the gas source and the gas conduit and being arranged to allow flow of propellant from the reduction valve to the container but to prevent flow of beverage from the container to the reduction valve.